Yo siempre digo la verdad.
You can use any form of the verb, but it has to be indicative. I have used the <u>present form</u> (the most used in these cases) of the verb "decir" (say).
Answer:
Digo.
Explanation:
No quiero comer fruta ni ensalada
what is the audio ? it says based on the audio :)
Nunca
No voy a la playa nunca.
B nunca