Use the Following Table for a Hypothetical Single-Product Economy Refer to the Data

Use the following table for a hypothetical single-product economy. $\begin{array}{c}\begin{array}{c}\\\underline{\text { Year }} \\ 1 \\2 \\3 \\4\end{array}\begin{array}{c}\text {Units of}\\\underline{\text { Output}}\\10\\12\\15\\20\end{array}\begin{array}{c}\text { Price of Bagel}\\\underline{\text { Per Unit}}\\\$ 10\\20\\ 30\\ 40\end{array}\begin{array}{c}\text {Price Index}\\\underline{\text {( Year 1=100) }}\\100\\200\\300\\400\end{array}\end{array}$
Refer to the data.Real GDP in year 3 is:

A) $100.
B) $450.
C) $225.
D) $150.