Learning English seems easy _______, but it is not really easy if you want to learn it well.[ ]

A. at last

B. at most

C. at least

D. at first

机关、团体、企业、事业等单位以及村民委员会、居民委员会根据需要，建立志愿消防队等多种形式的消防组织，开展群众性自防自救工作。