Complete the analogy by matching an object with the typical sound associated with its use: “Telephone : Ring :: ________ : ________”. Choose the pair that best mirrors the source → characteristic sound relationship.

Introduction / Context:
Analogy items frequently encode a relationship such as cause → effect, source → product, or object → characteristic sound. In the stem, “Telephone : Ring,” the first term is an object and the second is the typical sound associated with its activation or use. Your task is to select the option that preserves the same mapping.

Given Data / Assumptions:

• Telephone produces a “ring” when it receives a call.
• We seek an everyday object that has a conventional, strongly associated sound.
• The best answer should match the direction and type: object → characteristic sound.

Concept / Approach:
“Door : Knock” mirrors the structure neatly. A knock is the conventional sound that occurs when someone strikes a door to gain attention. It is as prototypical as “telephone : ring.” Other distractors either lack a sound mapping or reverse/change the relation (e.g., “Gate : Open” is an action, not a sound; “Door : Wood” is material composition, not sound; “Lock : Key” is an object–object pairing).

Step-by-Step Solution:
1) Identify the relation: object → characteristic sound.2) Evaluate each choice for a sound that is standardly linked to the object.3) Select “Door : Knock,” which preserves both direction and type.

Verification / Alternative check:
Common-sense usage confirms that knocking pertains specifically to doors (and similar surfaces) to signal presence, just as ringing is tied to telephones to signal an incoming call.

Why Other Options Are Wrong:

• Gate : Open — action/result, not a sound.
• Door : Wood — material composition relation, not auditory.
• Lock : Key — complementary objects; no distinctive sound mapping.

Common Pitfalls:
Picking an associated action or material instead of a characteristic sound can break the analogy type. Always preserve both the direction (object → sound) and the semantic category (sound).

Final Answer:
Door : Knock