&lt;?php$color = &quot;red&quot;;echo &quot;$color&quot;;echo &quot;$COLOR&quot;;echo &quot;$Color&quot;;?&gt;
A. redredred
B. redred
C. red
D. Error
Answer:A
&lt;?php$color = &quot;red&quot;;echo &quot;$color&quot;;echo &quot;$COLOR&quot;;echo &quot;$Color&quot;;?&gt;
A. redredred B. redred C. red D. Error
Explanation: In PHP, all variables are case-sensitive.