Which factor is likely to impact the possible number of compounds?

The correct answer is the tendency of all the elements to react with every other element.  

Explanation:

A component in which two or more elements are bonded chemically leads to the production of a compound. A compound refers to a pure component as it comprises elements that are in their pure state. The formation of a compound takes place when the elements react with each other based upon their reactivity.  

For example, the element chlorine is deficient of one electron and the element sodium exhibits one additional electron. Thus, chlorine easily reacts with the sodium in order to obtain stability. Therefore, the formation of sodium chloride takes place. Hence, it can be concluded that the tendency of all the elements to react with every other element is the condition, which is possible to influence the probable number of compounds.

i'm pretty sure it is letter c.) car