Answer:
C. am feeling
Step-by-step explanation:
"I am feeling good today".
When showing an ongoing action which is actually in progress, then the use of the progressive form of verb tense is necessary.
In progressive form of verb, "-ing" is added to the auxilliary verb. It is a form of a helping verb.
Other examples include:
"I am going home today"
"I am coming back now", etc.