Analysis of the Sentence
1. The Axiom: "Still waters run deep" means that a calm or reserved appearance (the "still waters") often conceals a passionate, intelligent, or complex nature (running "deep").

2. The Relationship: The convict's case _______ (i) this axiom. The statement following the colon explains how the axiom applies: his calm appearance (façade) should not imply a lack of remorse (deep feelings). Therefore, the case supports the axiom.

3. Blank (i): The Relationship to the Axiom (Must mean support/validation)
- (A) credence: Belief in or acceptance of something as true. If the axiom finds credence, it is validated or supported by the case. (Good Fit)
- (B) antagonism: Active hostility or opposition. (Contradicts the supporting role of the case.)
- (C) ambiguity: The quality of being open to more than one interpretation. (The case is being used to clarify the axiom's truth, not its ambiguity.)

4. Blank (ii): The Convict's Façade (Must mean a calm/reserved appearance)
- Context: The façade is the "still waters" part of the axiom, and it should not imply a lack of remorse (the "deep" part). The façade must be the outward show of emotional stillness.
- (D) contrition: The state of feeling remorse or penitence. (This is the opposite of the façade; remorse is the hidden feeling.)
- (E) bemusement: A state of being puzzled or confused. (Does not suggest emotional stillness.)
- (F) stoicism: The endurance of pain or hardship without the display of feelings and without complaint; emotional impassiveness. (Excellent Fit. This describes the calm, reserved exterior or "still waters.")