To find the quotient of \( 1,720 ÷ 10^3 \), we first calculate \( 10^3 \):
\[ 10^3 = 1000 \]
Now, we divide \( 1,720 \) by \( 1,000 \):
\[ 1,720 ÷ 1,000 = 1.72 \]
Thus, the quotient is:
\[ 1.72 \]
It appears that the closest correct representation in the responses is 1.720.