我觉得是C
free与ballon之间是主动关系,应该是ing形式.
句子意思：挣脱了冰块的束缚,气球爬升起来飘向南方.
句子开头用doing或者done或者to do?其实你的问题没问清楚.我猜你是在问作状语的成分放在句子开头,这些状语的成分.他们可以是doing、done构成的短语,也可以是介词构成的短语,但是没有to do.
比如：Being ill for too month,he died today.
left alone,he had to do it by himself.
without paper,he had to write it on her hand.
PS:多看语法书.