Crown gall is a disease caused by the bacterium Agrobacterium tumefaciens (synonym Rhizobium radiobacter), which enters the plant through wounds in roots or stems and stimulates the plant tissues to grow in a disorganized way, producing swollen galls. As the disease progresses, plants lose vigour and may eventually die.

Correct Option: B

Crown gall is a disease caused by the bacterium Agrobacterium tumefaciens (synonym Rhizobium radiobacter), which enters the plant through wounds in roots or stems and stimulates the plant tissues to grow in a disorganized way, producing swollen galls. As the disease progresses, plants lose vigour and may eventually die.

Xylem is one of the two types of transport tissue in vascular plants, phloem being the other. The basic function of xylem is to transport water from roots to shoot and leaves, but it also transports some dissolved nutrients. Together with phloem (tissue that conducts sugars from the leaves to the rest of the plant), xylem is found in all vascular plants.

Correct Option: A

Xylem is one of the two types of transport tissue in vascular plants, phloem being the other. The basic function of xylem is to transport water from roots to shoot and leaves, but it also transports some dissolved nutrients. Together with phloem (tissue that conducts sugars from the leaves to the rest of the plant), xylem is found in all vascular plants.

DDT is a persistent organic pollutant that is readily adsorbed to soils and sediments, which can act both as sinks and as long-term sources of exposure affecting organisms. Besides, spraying pesticides like DDT on plants pollutes the ground water system which contaminates the entire food chain by severely affecting humans dependent on these.

Correct Option: C

DDT is a persistent organic pollutant that is readily adsorbed to soils and sediments, which can act both as sinks and as long-term sources of exposure affecting organisms. Besides, spraying pesticides like DDT on plants pollutes the ground water system which contaminates the entire food chain by severely affecting humans dependent on these.

Kharif crops or monsoon crops are domesticated plants cultivated and harvested during the rainy (monsoon) season in the South Asia, which lasts between April and October. Kharif crops are usually sown with the beginning of the first rains in July, during the south-west monsoon season and harvested in September-October. Main kharif crops are millet and rice.

Correct Option: C

Kharif crops or monsoon crops are domesticated plants cultivated and harvested during the rainy (monsoon) season in the South Asia, which lasts between April and October. Kharif crops are usually sown with the beginning of the first rains in July, during the south-west monsoon season and harvested in September-October. Main kharif crops are millet and rice.

Reverse osmosis (RO) is a water purification technology that uses a semipermeable membrane to remove ions, molecules, and larger particles from drinking water. It can remove many types of dissolved and suspended species from water, including bacteria, and is used in both industrial processes and the production of potable water. It is most commonly known for its use in drinking water purification form.

Correct Option: D

Reverse osmosis (RO) is a water purification technology that uses a semipermeable membrane to remove ions, molecules, and larger particles from drinking water. It can remove many types of dissolved and suspended species from water, including bacteria, and is used in both industrial processes and the production of potable water. It is most commonly known for its use in drinking water purification form.