Plug-in type backfed circuit breakers connected to a stand-alone PV system are not required to be secured in place by an additional fastener that requires other than a pull to release the breaker from the panelboard.
See answer and applicable Code reference
The correct answer is: b) False
Article 690 requirements apply to solar PV systems. Circuit requirements are outlined in Part II of this Article. As noted in Sec. 690.10(E), "Plug-in type back-fed circuit breakers connected to a stand-alone inverter output in either stand-alone or utility-interactive systems shall be secured in accordance with 408.36(D). Circuit breakers that are marked "line" and "load" shall not be backfed."