Question

which of the following applies to spark plugs?
a) ignite the air - fuel mixture.
b) can affect the amount of voltage being delivered for combustion.
c) require replacement based on maintenance intervals.
d) all of the above.

Explanation:

Spark - plugs ignite the air - fuel mixture in an internal combustion engine. They can also affect the voltage delivered for combustion as their condition impacts the electrical discharge. And they do require replacement based on maintenance intervals.

Answer:

D. All of the above