Final Answer:
The word that can replace "reliance" without changing the meaning of the sentence is "dependence."
Step-by-step explanation:
"Reliance" and "dependence" are synonyms, and they share a similar meaning. Both words refer to the act of relying on or depending on something or someone. In the context of the sentence, replacing "reliance" with "dependence" would maintain the original meaning. The sentence would convey that the organization is dependent on its dedicated volunteers for its success. When looking for synonyms, it's important to consider the specific nuances of each word to ensure a precise match in meaning.
The word that can replace "reliance" without changing the meaning of the sentence is "dependence."