是Ahelp sb. with sth 帮助某人做某事 With pleasure 很乐意B选项的"A pleasure"是不完整的,如果是it's a pleasure就对了
help sb with sth 帮助某人做某事With pleasure! 乐意效劳A
就是Awith pleasure 是副词,可单独使用,意为ad. 愉快地(高兴地,十分愿意)
额...貌似是A 啊