Correct Answer: confused

Solution : The most appropriate synonym is the fourth option.

Explanation : In the context of the given word "puzzled", the key aspect to consider is the sense of confusion or uncertainty. "Confused" accurately captures this meaning, as it denotes a state of being unclear or bewildered.

Therefore, "confused" is the most appropriate synonym, aligning with the intended meaning of uncertainty or confusion associated with being puzzled.

The meanings of the other options are as follows:

• Sure : This term denotes confidence and certainty.
• Certain : This word signifies a high degree of confidence and assurance.
• Doubtless : This term implies a lack of doubt.