&lt;?php$color1 = &quot;red&quot;;$color2 = &quot;green&quot;;echo &quot;$color1&quot; . &quot;$color2&quot;;?&gt;
A. red
B. green
C. red green
D. redgreen
Answer:A
&lt;?php$color1 = &quot;red&quot;;$color2 = &quot;green&quot;;echo &quot;$color1&quot; . &quot;$color2&quot;;?&gt;
A. red B. green C. red green D. redgreen
Explanation: The . operator is used to join to strings.