With the Production Function $Y _ { t } = A _ { t } K _ { t } ^ { 1 / 3 } L _ { t } ^ { 2 / 3 }$

Multiple Choice

With the production function $Y _ { t } = A _ { t } K _ { t } ^ { 1 / 3 } L _ { t } ^ { 2 / 3 }$ , if we double ________, we have a constant returns production.

A) capital
B) capital, labor, and the stock of ideas
C) capital and the stock of ideas
D) capital and labor
E) labor and the stock of ideas