The current word is displayed as 'o___en', a six‐letter word with letters o, e, n already revealed and letters a, e, n, o, r, t guessed. One likely possibility is the word 'oxygen', which fits the pattern o-x-y-g-e-n. To test this, I'll try guessing a letter that appears in 'oxygen' but hasn’t been guessed yet. 'G' is common and would help reveal the hidden letter if the word is indeed 'oxygen'. Therefore, I choose 'g'.