どちら（どちら）— which of two; which way (polite)
海 と 山 と どちら が 好き ですか。
Which do you prefer, the sea or the mountains?
どちらどちら
which of two; which way (polite)
どちら
accent [1]In detail
Words
海umisea
とtoand (first option)
山yamamountains
とtoand (second option)
どちらdochirawhich of the two
がga(marks the choice being asked about)
好きsukiliked
ですdesu(polite sentence ending)
かka(question marker)
どちら asks which of two options in this sentence. It can also ask a direction or politely ask about a place. どっち is more casual.
Coco-sensei