Explanation:

- Option 1: Fluorecence

This is misspelled. The correct spelling is "Fluorescence," which refers to the emission of light by a substance that has absorbed light or electromagnetic radiation.

- Option 2: Forebear

This is correctly spelled. "Forebear" refers to an ancestor or forefather.

- Option 3: Forgo

This is correctly spelled. "Forgo" means to do without or abstain from something.

- Option 4: Flounder

This is correctly spelled. "Flounder" means to struggle or stagger clumsily.