Final answer:
The phrase 'innate desire to acquire a thorough knowledge' refers to a natural curiosity to gain comprehensive information, which is option (a).
Step-by-step explanation:
The meaning of the phrase "innate desire to acquire a thorough knowledge" is best explained as a natural curiosity to gain comprehensive information. This phrase indicates an inborn or inherent urge to deeply understand a subject or various aspects of the world. It reflects an eagerness for extensive learning and the pursuit of understanding that is driven by an internal motivation rather than external pressures or superficial interests.
Therefore, the answer to the question would be option (a) A natural curiosity to gain comprehensive information. This option correctly captures the essence of an innate desire which is a deep-seated drive, and a thorough knowledge, which implies a comprehensive and complete understanding of a subject. None of the other options suggest a natural, in-depth interest in learning, making (a) the best choice.