Cover crops, strip cropping, vegetative barriers are

Correct option is A

Cover crops, strip cropping, and vegetative barriers are practices that involve crop and vegetation management on agricultural land. These methods help in reducing soil erosion, conserving moisture, and improving soil structure naturally. Hence, they are classified under agronomic and soil management practices.
Information booster: Agronomic practices focus on proper use of crops and cropping systems to protect soil and enhance productivity. Cover crops protect soil surface from rainfall impact and runoff, thereby reducing erosion losses. Strip cropping and vegetative barriers slow down water flow and trap soil particles on sloping lands. These practices are eco-friendly and form an important part of soil and water conservation programmes.
Why other options are incorrect: (b) Engineering practices involve construction of structures like bunds and terraces, not crops or vegetation. (c) Chemical practices involve use of soil conditioners and chemicals, which is not applicable here. (d) None of these is incorrect because option (a) correctly describes these practices.