Which river forms the boundary line between Uttar Pradesh and Haryana?
a)Sutlej
b)Yamuna
c)Ganga
d)Parvati

Hint: Uttar Pradesh and Haryana are two states in northern India. Both the states are part of Indo Gangetic plains and are well drained by many rivers.

Complete answer: The state of Haryana has geographic features like the Yamuna-Ghaggar plains, Aravali ranges, lower Shivalik hill and the Bagar tracts. Uttar Pradesh on the other hand,has the Gangetic plain and a small part of Vindhya range and plateau in its southern end.

Let us look at the options given to us
Option (A) Sutlej rises in the Tibetan Plateau, joins Beas at Harika and forms the Panjnad as it joins Chenab. The Panjnad finally joins Indus and empties itself in Arabian Sea. The river flows through the states of Punjab and Himachal Pradesh in India.
Option (B) Yamuna originates in Yamunotri glacier and joins Ganga at Prayagraj. The Yamuna flows through Uttarakhand, Himachal Pradesh, Haryana ,Uttar Pradesh and Delhi. After passing through Paonta Sahib in Himachal Pradesh, it flows along the Haryana and Uttar Pradesh boundary before joining Ganga at Allahabad.
Option (C ) Ganga forms through the confluence of Alaknanda and Bhagirathi and then flows as Ganga and enters the plains at Haridwar. The Ganga basin covers the states of Uttarakhand, U.P., M.P., Rajasthan, Haryana, Himachal Pradesh, Chhattisgarh, Jharkhand, Bihar, West Bengal and Delhi.
Option (D) Parvati river flows in Himachal Pradesh in Parvati valley and joins Beas which is a tributary of Indus.

Therefore, the correct answer is option (B).

Note: Sind, Betwa, Tons, Chambal, Ken are Yamuna’s tributaries. Chambal is its longest tributary. One should also note that Yamuna flows along the boundary of Himachal Pradesh and Uttarakhand.