D. It needs a comma before and.
Answer:
Explanation:
"Instinctual" appears more frequently in scientific writing and refers to the notion of behavior itself, while "instinctive" may sometimes be reserved to describe specific behaviors. ... Instinctive is defined as “of, relating to, or being instinct” and “prompted by natural instinct or propensity : arising spontaneously.”
The past tense of cost is usually “cost”.
Very rarely is the past tense “costed” used, it’s more common to just say cost.
