Explain the relationship between the environment, variation, and selection. changing can cause certain traits to be favored through . this can lead to changes in .

Ithink the answer is a

  i think you forgot to put the options but if your reffering to this question then your answer will be "b"  a. add "to" to the base form to create an adjective.b. when the subject of a sentence is singular, add "–s" to the base form.c. add "–ed" to irregular base forms to form the past participle.d. do not use a base form with plural subjects