The correct choice is (a) Queen post truss
To explain: A queen post truss has two principal rafters and two vertical queen posts. The queen post truss extends the span, and combined with spliced joints in the longer members extends the useful span for trusses of these types. As with a king post, the queen posts may be replaced with iron rods and thus called a queen rod truss. This truss is often known as a palladiana (Palladian truss) in Italy, as it was frequently used by the Venetian architect Andrea Palladio. Sometimes a palladian truss is defined as a compound truss with a queen post and king post truss in the same assembly.
The queen post truss and the king post truss may be combined, by using the straining beam of the queen post truss as the tie beam for a king post truss above. Such combinations are known as compound trusses.