In a plant , tallness is dominant over dwarfness and red flowers are incompletely dominant over white flowers, the hybrid being pink. How many offsprings will be of tall height with pink flowers from a cross involved two plants each of which is hybrid tall and has pink flowers ?

Options

A. `4/16`
B. `6/16`
C. `10/16`
D. `2/16`

Answer

To solve the problem, we need to determine the number of offspring that will be tall with pink flowers when crossing two hybrid tall plants with pink flowers.

### Step-by-Step Solution:

1. **Identify the Traits and Alleles:**
- Tallness (T) is dominant over dwarfness (t).
- Red flowers (R) are incompletely dominant over white flowers (r), resulting in pink flowers (Rr).

2. **Determine the Genotypes of the Parent Plants:**
- Since both parent plants are hybrid tall and have pink flowers, their genotypes will be:
- Tall: Tt (where T = tall, t = dwarf)
- Pink: Rr (where R = red, r = white)

3. **Set Up the Punnett Square:**
- We will create a Punnett square for the cross TtRr x TtRr.
- The gametes from each parent will be:
- Parent 1: TR, Tr, tR, tr
- Parent 2: TR, Tr, tR, tr

4. **Fill in the Punnett Square:**
- The combinations will be:
```
| | TR | Tr | tR | tr |
|---|----|----|----|----|
| TR| TTRR | TTRr | TtRR | TtRr |
| Tr| TTRr | TTrr | TtRr | Ttrr |
| tR| TtRR | TtRr | ttRR | ttRr |
| tr| TtRr | Ttrr | ttRr | ttrr |
```

5. **Determine the Phenotypes:**
- From the Punnett square, we can identify the phenotypes:
- TTRR: Tall, Red
- TTRr: Tall, Pink
- TtRR: Tall, Red
- TtRr: Tall, Pink
- TTrr: Tall, White
- Ttrr: Tall, White
- ttRR: Dwarf, Red
- ttRr: Dwarf, Pink
- Ttrr: Tall, White
- ttrr: Dwarf, White

6. **Count the Tall Pink Offspring:**
- From the filled Punnett square, we identify the tall pink phenotypes:
- TTRr: 2 occurrences
- TtRr: 4 occurrences
- Total tall pink offspring = 2 + 4 = 6.

7. **Calculate Total Offspring:**
- The total number of offspring combinations is 16 (4x4 Punnett square).
- The ratio of tall pink offspring is 6 out of 16.

### Final Answer:
The number of offspring that will be tall with pink flowers is **6**.