D Grade- only applies to senior year?

<p>So the UCs say that a grade below C is not acceptable. They say if we have a D in our Senior year, we must report it immediately with an appropriate explanation. I was wondering, does this apply for Junior year as well? Or do they only care about 12th grade grades? Cause I have a D from my second semester of chemistry in 11th grade.
I got accepted to UC Davis and I was wondering if I have to submit an explanation for this grade? </p>

<p>They already saw the one in your junior year and took it into account in your acceptance.</p>