Torborg Corp $\begin{array}{lrr} \text { Short-term Equity Investments } &3,600\\ \text { Unrealized Gain} &&3,600\\\end{array}$

Torborg Corp. purchased short-term passive investments in equity securities on December 23 for $3,000. On December 31, the market value of those securities is $3,600. Which one of the following journal entries is appropriate on December 31?
a.
$\begin{array}{lrr} \text { Short-term Equity Investments } &3,600\\ \text { Unrealized Gain} &&3,600\\\end{array}$

b.
$\begin{array}{lrr} \text { Short-term Equity Investments} &600\\ \text { Unrealized Gain } &&600\\\end{array}$


c.
$\begin{array}{lrr} \text { Short-term Equity Investments } &600\\ \text { Unrealized Price Increase } &&600\\\end{array}$


d. $\begin{array}{lrr} \text { No entry is required. } &\\\end{array}$