Long study sessions need the right study drink with it; it can keep you focused and also provide continuous source of energy.
My personal favourites are coffee, fruit teas, ice tea and sometimes water is just enough.
What’s your go-to study drink, and why? 
MBH/AB
For me water is just enough it keeps me hydrated and fresh.
Interesting, Popular study-time drinks like coffee and energy beverages might help you stay alert but caffeine shots can spike your heart rate, disrupt sleep, and lead to jitters. On the other hand, hydration matters: even mild dehydration can harm concentration and memory. Herbal teas like peppermint or green tea offer a gentler boost, and even a quick water break can help clear your mind mid-study.
Water is the best drink as it refreshes the body and helps clear unnecessary thoughts while studying.
no doubt it would be coffee. it makes me feel more concentrated and helps to stay alert. not frequently but especially if i have any difficult subject or topic to deal with i prefer coffee. Mostly i drink water or water-based drinks like chia water or detox waters using cucumbers or mint which feels refreshing.
I would say Tea for me.
only water
I personally prefer water and fresh fruit juices.