Select the word you consider most appropriate to fill in the blank space. My son is very ___ ; he trusts everyone.

Step-by-step solution

'Gullible' will be used in the blank space as the context of the blank is easily persuaded to believe something Gullible: easily persuaded to believe something; credulous. Fallible: capable of making mistakes or being wrong. Credible: able to be believed; convincing. Sensible: done or chosen in accordance with wisdom or prudence; likely to be of benefit. Hence, B is the right answer choice.