Out of 'X' pairs of ribs in humans only 'Y' pairs are true ribs. Select the option that correctly represents values of X and Y and provides their explanation

Options

A. x=12 , y=7 True ribs are attached dorasally to vertevral column and ventrally to the sternum
B. x=12, y=5 True ribs are attached dorasally to vertevral column and sternum on the two ends
C. x=24, y=7 True ribs are attached dorasally to vertevral column but are free on ventral side
D. x=24, y=12 True ribs are attached dorasally to vertevral column but are free on ventral side

Explanation

To solve the question about the number of rib pairs in humans and the classification of true ribs, we can break it down into the following steps:

### Step 1: Understand the Total Number of Rib Pairs
Humans have a total of **12 pairs of ribs**. This means that there are 24 individual ribs, but since the question refers to pairs, we will use the number of pairs.

### Step 2: Classify the Ribs
The 12 pairs of ribs are classified into three categories:
- **True Ribs**: These are the first 7 pairs (1st to 7th). They directly connect the vertebral column to the sternum.
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