Question: What type of genre do The Bluebells and Monoral have in common?

Context paragraphs:
Bluebell wood: A bluebell wood is a woodland that in springtime has a carpet of flowering bluebells ("Hyacinthoides non-scripta") underneath a newly forming leaf canopy.  The thicker the summer canopy, the more the competitive ground-cover is suppressed, encouraging a dense carpet of bluebells, whose leaves mature and die down by early summer.  Other common woodland plants which accompany bluebells include the yellow rattle and the anemone.

Monoral: Monoral is a Japanese alternative rock band signed to Sony Music Japan.  The band consists of Anis Shimada on lead vocals and guitar and Ali Morizumi on bass and guitar.

Phacelia campanularia: Phacelia campanularia is a species of flowering plant in the borage family, Boraginaceae, known by the common names desertbells, desert bluebells, California-bluebell, desert scorpionweed, and desert Canterbury bells.  Its true native range is within the borders of California, in the Mojave and Sonoran Deserts, but it is commonly cultivated as an ornamental plant and it can be found growing elsewhere as an introduced species.

Mertensia longiflora: Mertensia longiflora is a species of flowering plant in the borage family known by the common names small bluebells and long bluebells.

Mertensia oblongifolia: Mertensia oblongifolia is a species of flowering plant in the borage family known by the common names oblongleaf bluebells and sagebrush bluebells.

The Bluebells: The Bluebells were a Scottish indie rock band, active between 1981 and 1986 (later briefly reforming in 1993, 2008–2009 and 2011).

Mertensia ciliata: Mertensia ciliata is a species of flowering plant in the borage family known by the common names tall fringed bluebells, mountain bluebells, and streamside bluebells.

Eustoma russellianum: Eustoma russellianum, is a species of flowering plant in the Gentian family.  Its previous binomial name was "Eustoma grandiflorum".  Common names include Texas bluebells, Texas bluebell, bluebell, showy prairie gentian, prairie gentian The Bolero Deep Blue, and Lisianthus.

Mertensia bella: Mertensia bella is a species of flowering plant in the borage family known by the common names beautiful bluebells and Oregon lungwort.  It is native to the northwestern United States, where it grows in wet mountain habitat.  It is a perennial herb producing a slender, erect stem and caudex unit up to half a meter tall.  The rough-haired leaves are alternately arranged and borne on petioles.  The inflorescence is an open array of clustered bright blue, bell-shaped flowers up to a centimeter wide at the lobed mouths.

Mertensia maritima: Mertensia maritima a species of flowering plant in the borage family known by the common names oysterleaf, oysterplant or sea bluebells.

Supporting paragraphs: The Bluebells Monoral
Answer: rock