Digital signature for sole proprietorship

A person is running sole proprietorship business and is liable for tax audit. For filing of ITR, should be use digital signature in his personal name or in the name of the business he is running?

For example, his shop name is Arun Fruits and his personal name is Arun Singh. Then should he get a digital signature in the name of Arun Fruits or digital signature in his personal name would be fine?

Thanks in advance.