Slect the option that correctly fills up the blanks in the given paragraphs After one month of pregnancy the embryo's (i)._____is formed By the end of the (ii)._____month of pregnancy the fetus develops limbs and digits. By the end of (iii)._____most of the major organ systems are formed, for example, the limb and external genital organs are well-developed by the end of (iv)._____the body is covered with fine hair, eye-lids separate, and eyelashed are formed

Options

A. (i)- heart, (ii)- second
(iii)- first trimester, (iv)- second trimester.
B. (i)-heart, (ii)-second
(iii)-first month, (iv)-second month
C. (i)-heart, (ii)- second,
(iii) first week, (iv)- second week
D. (i)-heart, (ii)-fourth
(iii). First trimester, (iv)- second trimester

Answer

To fill in the blanks in the given paragraphs about human embryonic development during pregnancy, we can follow these steps:

1. **First Blank (i)**: After one month of pregnancy, the embryo's **heart** is formed.
- Hint: The heart is one of the first organs to develop in the embryo.

2. **Second Blank (ii)**: By the end of the **second** month of pregnancy, the fetus develops limbs and digits.
- Hint: The development of limbs and digits occurs in the early stages of pregnancy, specifically around the second month.

3. **Third Blank (iii)**: By the end of the **first** trimester (which is three months), most of the major organ systems are formed.
- Hint: The first trimester is crucial for organ development, and it lasts until the end of the third month.

4. **Fourth Blank (iv)**: The limb and external genital organs are well-developed by the end of the **second** trimester (which is six months).
- Hint: The second trimester is when significant development of limbs and external genitalia occurs.

5. **Final Statement**: By the end of the second trimester, the body is covered with fine hair, eyelids separate, and eyelashes are formed.
- Hint: The second trimester is also characterized by the development of fine hair (lanugo) and facial features.

So, the completed paragraph would read:
"After one month of pregnancy the embryo's (i) heart is formed. By the end of the (ii) second month of pregnancy the fetus develops limbs and digits. By the end of (iii) the first trimester most of the major organ systems are formed, for example, the limb and external genital organs are well-developed by the end of (iv) the second trimester. The body is covered with fine hair, eyelids separate, and eyelashes are formed."

### Summary of Answers:
(i) heart
(ii) second
(iii) first
(iv) second