sentence1: Why do we need a starter to start an AC and DC m/c ?
sentence2: `` Kirchhoff '' `` s law is applicable to - -LRB- A -RRB- passive networks only -LRB- B -RRB- AC circuits only -LRB- C -RRB- DC circuits only -LRB- D -RRB- both AC as well as DC circuits ? ''