Secretly is to openly as silently is to ____.

Given data

• Secretly and openly are opposites.
• Silently has a direct opposite in manner of sound.

Concept/Approach

Preserve the antonym pattern: manner adverb contrasted with its opposite.

Step-by-step reasoning
Secretly ↔ openlySilently ↔ ?Opposite of silently = loudly

Verification/Alternative

Quietly is a near synonym; slowly and stealthily do not oppose silence.

Common pitfalls

Choosing a synonym rather than an antonym.

Final Answer
loudly