We gathered all the tools and equipment we would need to.
A. Change gathered to gather
B. Delete the word to
C. Add have after would
The correct answer is A. Change "gathered" to "gather."
In this sentence, we are talking about an action that has already taken place. Therefore, the past participle form "gathered" should be changed to the base form "gather," which indicates the simple past tense. Removing the word "to" or adding "have" after "would" would alter the meaning or grammatical structure of the sentence.