Answer: b) [tex]\dfrac{1}{6}[/tex]
Step-by-step explanation:
Sample space for the arrangement of red bushes :
[rrww , rwwr , wwrr , wrwr, rwrw , wrrw]
i.e. Total possible outcomes = 6
If the two rosebushes middle of the row are red , then the first and the last rosebushes must be white (wrrw).
i.e. the number of favorable outcomes for middle of the row are red =1
Now, the probability that the 2 rosebushes in the middle of the row will be the red rosebushes :
[tex]\dfrac{\text{Favorable outcomes}}{\text{Total outcomes}}\\\\=\dfrac{1}{6}[/tex]
Hence, the correct answer is option (b).