Knowledge of biology can promote advances by our people make

b

is correct hope this   also i learnd this in middle school

preservation because he preserves part of the land and preserves means save

explanation:

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.