Which term means to picture falsely or misrepresent?

The term that means to picture falsely or misrepresent is "belie." When something belies another, it suggests a contradiction between the two, often implying that an appearance, statement, or impression is not true or is misleading. This term is frequently used in contexts where someone's outward behavior or claims do not accurately represent their true feelings, intentions, or the reality of a situation. For instance, if someone's cheerful demeanor belies their inner sadness, it means that their outward appearance misrepresents their actual emotional state.

The other terms present distinct meanings. "Bellicose" refers to a tendency to fight or be aggressive, while "assiduous" signifies being diligent and hardworking. "Approbation" refers to official approval or praise, which is unrelated to the concept of misrepresentation. Thus, "belie" is the most fitting choice in this context.