Step 1: Understanding the Concept
Reflexes may be unconditional (inborn) or conditional (learned). They may be simple or complex depending on the pathway.
Step 2: Apply to swimming
Swimming is learned by practice after birth, so it is conditional. It needs many sensory and motor neurons, interneurons and many muscle groups, so it is complex and polysynaptic.
Step 3: Why the other options fail
Swimming is not inborn, so unconditional options are wrong. It also involves many synapses, so simple monosynaptic options are wrong.
Final Answer:
Swimming is a complex, polysynaptic, conditional reflex.
\[ \boxed{\text{(C) }\text{complex, polysynaptic, conditional}} \]