What provides support to the main idea of a text?

EVIDENCE

Explanation

Evidence of the main idea includes the words, phrases, and sentences within the original text that repeat or reiterate the sentiment of the main-idea sentence.

the  seven  days  battles  were  a series of seven battles over seven  days from june 25 to july 1, 1862, near richmond, virginia,  during  the american civil war. the  seven  days ended with mcclellan's army in relative safety next to the james river, having suffered almost 16,000 casualtiesduring  the retreat.