Could be B or D but the most likely answer would be D
I assume you mean the three tenses, but let me know if you need more.
Past Tense: "Birds flew in the sky."
Future Tense: "Birds will fly in the sky."
The sentence is already in the present tense.
Determined is defined as <span> having a strong feeling that you are going to do something and that you will not allow anyone get in your way.
Stubborn is defined as </span><span>having or showing dogged determination not to change one's attitude or position on something, especially in spite of good arguments or reasons to do so.
Connotation of determined and stubborn is being strong-willed and resolute. When you are determined, you have decided to do something. When you are stubborn, in doing what you have to do and presented with arguments, you still decided to continue what you are doing regardless of what others say.
</span>
The answer (after 2 hours of deciphering...) is
"THE TONGUE IS THE ONLY INSTRUMENT THAT GETS SHARPER"
Hope I could help, this was a tough one.
