The signal man assisting the crane operator has his arm extended, with the thumb pointing up, and is flexing his fingers in and out for as long as the load movement is desired. This is the signal to __________.

Correct Answer: Option A — raise the boom and lower the load

Standard crane hand signals designate an arm extended with the thumb pointing up and flexing fingers in and out as the command to raise the boom while simultaneously lowering the load to maintain safe cargo handling control.