Answer:
我在学习中文 (I'm Studying Chinese)
Explanation:
汉字 (Hanzi) is the Chinese character used in the chinese language. While, 中文 translates as chinese language or could also be 华文 (hua wen) which is also like 中文, but using 华文 is more preferable. 我在学习华文 or 我在学习中文 is both correct. :)