Which statement is true regarding the disadvantages of Wheel Lock firearms?

The statement regarding the disadvantages of Wheel Lock firearms, highlighting that their mechanisms are complex and expensive to make, accurately reflects the historical and technical challenges associated with these firearms. Wheel Lock mechanisms, which utilize a rotating wheel to create sparks for ignition, are intricate and require precise engineering. This complexity not only makes them more costly to manufacture compared to simpler ignition systems but also contributes to potential reliability issues.

In contrast, the other choices do not align with the disadvantages of Wheel Lock systems. For instance, while ease of maintenance or lightweight design may be desirable features in other types of firearms, Wheel Locks are generally less convenient to maintain due to their intricate components. The assertion about a fast ignition system does not apply either, as the ignition mechanism in a Wheel Lock can be slower compared to more modern systems like flintlocks or percussion locks. Thus, the mechanical complexity and cost truly represent significant disadvantages for Wheel Lock firearms.