**Core Concept**
Chorionic villi sampling (CVS) is a prenatal diagnostic test that involves removing a small sample of cells from the placenta to detect genetic abnormalities or chromosomal disorders in the fetus. The procedure is typically performed between 10 and 12 weeks of gestation.

**Why the Correct Answer is Right**
The most appropriate time for CVS is between 10 and 12 weeks of gestation, as the placenta is fully formed and the risk of miscarriage is lowest during this period. The procedure is usually performed after the first trimester, when the risk of misdiagnosis due to mosaicism is minimized. The cells obtained from CVS contain the same genetic material as the fetus, allowing for accurate diagnosis of genetic disorders.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because CVS is not performed during the first 8-10 weeks of gestation, when the placenta is still developing and the risk of miscarriage is higher.
**Option B:** This option is incorrect because CVS is not performed after 16 weeks of gestation, when the risk of miscarriage increases and the procedure becomes more invasive.
**Option C:** This option is incorrect because CVS is not performed during the second trimester, when the risk of miscarriage and the invasiveness of the procedure increase.

**Clinical Pearl / High-Yield Fact**
It's essential to note that CVS carries a small risk of miscarriage, and the procedure should be performed by an experienced practitioner to minimize this risk.

**Correct Answer:** C. 10-12 weeks of gestation.