Question

which formula stands for boric acid?

name	symbol
borate	$bo_{3}^{-3}$
bromine	$br$
boron	$b$

$\bigcirc$ $h3b$\
$\bigcirc$ $h3bo3$\
$\bigcirc$ $hbr$\
$\bigcirc$ $h3po4$

Explanation:

硼酸是由硼（B）、氧（O）和氢（H）组成的酸，其化学式为$H_3BO_3$。$H_3B$不符合硼酸组成；$HBr$是氢溴酸；$H_3PO_4$是磷酸。

Answer:

$H_3BO_3$