The doctor treated the baby by giving him

a
an injection
b
a capsule
c
an ointment

a

The doctor treated the baby by giving him an injection.

To determine the correct answer to the question, we need to examine the given options:

a) an injection
b) a capsule
c) an ointment

Based on these options, the doctor likely treated the baby by giving him either an injection, a capsule, or an ointment.

To find the correct answer, we might consider the common treatments for babies that are commonly administered by doctors. One typical method is giving injections, which involves inserting a needle into the skin to deliver medication directly into the bloodstream. Another option is capsules, which are solid containers filled with medication that are swallowed. Lastly, ointments are topical treatments that are applied directly to the skin.

Since we do not have further information about the specific treatment or context, it is difficult to determine which exact method was used. However, the most common treatment among the three options for babies is usually an ointment or an injection.

Therefore, the doctor likely treated the baby by giving him either an injection or an ointment.