Explanation:
HIV is a decease that Is caused by sexual intercorse
Elaborate more if u need an answer
Carbon is transfered by plants and animals.
Gates function in a similar way as cell membrane :
cell membrane seperate the external enivironment from the cell while gate even seperate the external environment from the house
cell membrane controls the exit and entry of the cell, gate controls the entry and exit of the house
Explanation:
B is the right answer because none to the others sound like a real solution