Answer:
a. Selective attention/comprehension
Step-by-step explanation:
Selective attention/comprehension -
It refers to some specific external factors , which alerts someone's attention , is referred to as Selective attention/comprehension .
The factors can be some external factors like some specific words , activities , situation etc.
Hence , from the given scenario of the question ,
The students gets distracted by the sound of the pencil on desk .
The correct answer is a. Selective attention/comprehension .