A cracked motor block is most likely indicated by which of the following?

A cracked motor block is typically indicated by leaking engine coolant due to the significant stress and pressure that the engine block endures during operation. When a crack develops in the block, it can create a pathway for coolant to escape, often leading to noticeable leaks beneath the engine. This problem may also result in overheating, as the loss of coolant affects the car's ability to regulate its engine temperature effectively.

Other symptoms like the car not starting, engine sputters, or fouled spark plugs may be associated with various engine issues but are not specifically indicative of a cracked motor block. For example, a car not starting could result from many electrical or fuel-related issues. Similarly, engine sputtering could be tied to problems such as improper fuel delivery or ignition system failures. Fouled spark plugs often suggest issues with the air-fuel mixture or combustion process, rather than a structural failure of the motor block itself.