General exam question G8C08

WhyIn PSK31, upper case letters use longer Varicode bit sequences and thus slow down transmission. PSK31's Varicode character encoding assigns shorter bit sequences to common lowercase letters and longer sequences to less common characters including uppercase letters, so typing in all caps actually slows the effective transmission rate, answer B. Uppercase letters aren't sent with more power, PSK31 as commonly used doesn't include built-in error correction, and it isn't a mode that needs more power than RTTY for a comparable error rate, if anything the opposite is generally true, so A, C, and D are wrong.