Q.The structural reason corporate governance mechanisms are needed in a modern joint stock company is:

Governance mechanisms exist specifically to bridge the gap created when the people who own a company are not the same people who run it day to day. …

Corporate governance exists to solve a specific structural problem, and this question checks that the reason is correctly identified.

Option (a) is incorrect: even where government regulation is light, governance concerns can still arise purely from the internal relationship between owners and managers — regulation is not the root cause.

Option (c) is incorrect: company size is not the defining issue — even a very large company with concentrated ownership (where the owner also manages) has fewer governance concerns of this kind than a company where ownership is widely dispersed.

Option (d) is incorrect: most companies, especially large joint stock companies, are not family-owned, and even family-owned companies can still face governance issues once professional managers are brought in. …

Confusing this with a general "companies need rules" answer instead of identifying the specific structural feature — owner/manager sepa …