Final answer:
The correct pair of double reed instruments are the oboe and bassoon, with the oboe playing higher pitches and the bassoon lower pitches, which can be deduced by their sizes.
Step-by-step explanation:
Double reed instruments are a family of woodwind instruments that use two reeds vibrating against each other to produce sound. The oboe is known for its clear and penetrating voice, often playing high-pitched sounds, while the bassoon is larger and produces low-pitched sounds. When looking at two instruments you cannot identify by sound, you can often distinguish which one plays at a higher or lower pitch by their size; typically, the larger the instrument, the lower the pitch it produces.