有一天，一个女孩参加数学考试只得了 38 分。她心里对父亲的惩罚充满恐惧，于是偷偷把分数改成了 88...

The father broke down because he realized that his daughter is red-green colorblind. When he noticed that the "8" on her test paper was half green and half red, he initially thought she was trying to deceive him by altering the score. However, after she cried without explaining, he realized she couldn't distinguish between red and green—a sign of red-green color blindness.

In humans, red-green color blindness is a genetic condition linked to the X chromosome. It's rare in females because they have two X chromosomes, and the condition is typically recessive. For a girl to be red-green colorblind, she must inherit the defective gene from both parents. Since the father is not colorblind (he can distinguish the colors), he cannot pass the defective gene to her. This means the biological father must be colorblind. Realizing this, the father understood that he is not her biological father, leading to his emotional breakdown.

Answer: Because he realized his daughter is red-green colorblind—which she’d inherit only if he were colorblind—so he’s not her biological father, leading him to break down.

父亲之所以崩溃，是因为他意识到女儿患有红绿色盲。起初，父亲看到试卷上的“8”一半是红色，一半是绿色，认为女儿在改分数欺骗他，所以非常生气。然而，当女儿被打后委屈地哭泣却没有辩解，父亲开始怀疑。随后，他明白女儿可能无法区分红色和绿色，这正是红绿色盲的表现。

在遗传学上，红绿色盲是由X染色体上的基因缺陷引起的。女性有两条X染色体，要患上红绿色盲，必须同时从父母双方各遗传一个缺陷基因。如果父亲不是色盲（因为他能区分红色和绿色），那么按照遗传规律，女儿不可能患上红绿色盲。这意味着女儿的生物学父亲可能另有其人。意识到这一点后，父亲情绪崩溃了。

答案：因为父亲发现女儿患有红绿色盲，这意味着他可能不是她的亲生父亲，所以他崩溃了。