Which project is a Class B General Building contractor classified to take as the prime contract, rather than a specialty contractor?

解析

B&P §7057(a) defines the General Building contractor by the structure and by the use of at least two unrelated building trades, so the multi-trade custom home is the prime contract a Class B is classified to take. The other three are each a single trade belonging to a specialty class — C-39 roofing, C-8 concrete, C-10 electrical — and §7057(b) bars a Class B from taking a prime contract on a project involving a single trade other than framing or carpentry unless it holds that specialty classification.