Why can't I respond "all" to a text sent to a group?

When someone sends me a text and I am part of a group, when I respond it only goes to the person who sent it, instead of to everyone. Why? and how can I change that?

from Android Forums at AndroidCentral.com - Ask a Question //forums.androidcentral.com/ask-question/758389-why-can-t-i-respond-all-text-sent-group-new-post.html
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