ग्रेगर मेंडेल द्वारा वंशागति के नियमों को प्रतिपादित करने में किन दो विषयों के ज्ञान ने महत्वपूर्ण भूमिका निभाई?

A world chess champion has curly hair, attached earlobes, and freckles. Which one of the following traits is NOT likely to be passed on to his/her offspring?

Two children of the same parents resemble each other but are not exactly alike because __________.