At the tips of stems and roots produce rapid growth in plants.
a. apical growth
b. secondary growth
c. cells
d. meristem

The correct answer to the question above is (d.) Meristem. Meristem at the tips of stems and roots produce rapid growth in plants. Meristem is a tissue that is mostly found in plants. Meristematic cells are responsible for the plant's rise and to keep the plant growing.

answer: - b cells

explanation: -

there are many types of white blood cells present in our body. one such class of white blood cells are the lymphocytes. the b cells belong to the lymphocyte class of wbcs. the b cells perform their action against the pathogen by producing specialised proteins called as antibodies. these antibodies are produced as and when the b cells encounter pathogens in response to the antigens present on the surface of the pathogen. these antibodies bind to the antigens present on the pathogen and then, target them for destruction by other cells of the immune system.

so, the b cells mediate their action by identifying the antigens present on the surface of the pathogens and then producing antibodies in return to mediate its effect.

What are the choices?