The correct answer is A) It is normally the case where the main-emergency bus-tie circuit breaker and any on-line ship's service generator circuit breakers be simultaneously closed. This is the correct answer because it is a standard electrical configuration on ships to have the main-emergency bus-tie circuit breaker and the ship's service generator circuit breakers closed simultaneously. This allows the ship's service generators to provide power to both the main and emergency buses, ensuring redundancy and reliability of the electrical system. The other options are incorrect because: B) Simultaneous closure of the main-emergency bus-tie and emergency generator breakers would create a short circuit and is not allowed; C) The emergency generator is typically not connected directly to the main bus, but rather through the emergency bus; and D) Shore power is normally capable of feeding both main and emergency loads, not just emergency loads.