Answer:
I adamantly oppose the proposal for mandatory school uniforms.
Step-by-step explanation:
The phrase "adamantly oppose" is the one that presents the strongest persuasive appeal. To believe something "adamantly" means that you believe in this idea firmly, and are not at all open to changing your mind. In this example, the fact that the speaker believes in this view so strongly is persuasive, as it leads us to believe there must be strong reasons for him to hold this view.