Question: Which drink is considered a highball, a Rickey or a Greyhound?

Context paragraphs:
Screwdriver (cocktail): A screwdriver is a popular alcoholic highball drink made with orange juice and vodka.  While the basic drink is simply the two ingredients, there are many variations; the most common one is made with one part vodka, one part of any kind of orange soda, and one part of orange juice.  Many of the variations have different names in different parts of the world.  The International Bartender Association has designated this cocktail as an IBA Official Cocktail.

Agent Orange (cocktail): An Agent Orange is a highball drink made with carrot juice, vodka, and rum.  Consisting of only two ingredients, Agent Orange was first recorded as a drink at the 2007 San Mateo County Fair's cocktail competition held in San Mateo, California.  It won "Best New Cocktail of Fair" award.  Since 2007 it has become somewhat of a local favorite being offered in many hotels throughout the San Francisco Bay Area.  Because it generally uses organic carrot juice and Svedka Vodka as its prime components, it is usually only available in hotels serving organic juices.

Greyhound (cocktail): A greyhound is a cocktail consisting of grapefruit juice and either gin or vodka mixed and served over ice.  If the rim of the glass has been salted, the drink is instead called a salty dog.

Purple Rain (drink): The Purple Rain refers to at least two popular mixed drinks.  The more common is a variation on the highball Long Island Iced Tea, substituting Chambord for Triple Sec and a lemon-lime soda for the cola.  The other is a long cocktail made from vodka, lemonade, blue Curaçao and grenadine.  The name of this version originates from the appearance of the drink as the grenadine is added as the final ingredient, since the sinking of the red grenadine through the blue of the other ingredients creates the impression of purple rain.  This drink has many versions depending on where it is made.

Mick the Miller: Mick the Miller (29 June 1926 – 6 May 1939) was a male brindle Greyhound.  He is celebrated as the first great racing greyhound to compete in England (although he was born in Ireland).  Despite a short three year racing career, his achievements were highly publicised around the world and by the end of his career he had become an icon in the sport.  His achievements include winning nineteen races in a row, including the English Greyhound Derby on two successive occasions.  He suffered an injury at Wimbledon Stadium whilst racing which broke the streak in 1931, and once recovered was beaten in the attempt to win a third Derby title.  He went on to appear in films, and is still considered one of the greatest sporting heroes in the UK.

Piscola: Piscola or Combinado Nacional (national mix) is a highball cocktail, made of pisco and most commonly a cola drink, that is popular in Chile.  A piscola may be "black" or "white" depending if it is mixed with a cola or ginger ale, Tonic, Sprite or a similar soft drink.  The drink is prepared by filling a highball glass with ice and then adding pisco followed by the soft drink in a proportion ranging from 1:1 to 1:3.  Sometimes slices of lemon or key lime may be added.  In Chile, February 8 has been celebrated as the "day of the piscola" since 2003.

Chūhai: Chūhai (チューハイ or 酎ハイ ) , often sold as Chu-Hi as a canned drink, is an alcoholic drink originating from Japan.  The name chūhai is an abbreviation of "shōchū highball" (焼酎ハイボール).  Traditional chūhai is made with shōchū and carbonated water flavored with lemon, though some modern commercial variants use vodka in place of shōchū.  The flavors available have recently multiplied, including lime, grapefruit, apple, orange, pineapple, grape, kyoho grape, kiwi, "ume", "yuzu", lychee, peach, strawberry cream, and cream soda.

Salty dog (cocktail): A salty dog is a cocktail of tequila, or gin, and grapefruit juice, served in a highball glass with a salted rim.  The salt is the only difference between a salty dog and a greyhound.  Vodka may be used as a substitute for tequila; nevertheless, it is historically a tequila drink.

Rickey (cocktail): The rickey is a highball drink made from gin or bourbon, half of a lime squeezed and dropped in the glass, and carbonated water.  Little or no sugar is added to the rickey.  Originally created with bourbon in Washington, D.C. at Shoomaker's bar by bartender George A. Williamson in the 1880s, purportedly in collaboration with Democratic lobbyist Colonel Joe Rickey, it became a worldwide sensation when mixed with gin a decade later.

Saint Clement's (cocktail): The Saint Clement's is a non-alcoholic cocktail.  Though the ingredients may vary, it always consists of orange juice mixed with a lemon-flavored drink, usually in equal proportions; the name of the drink refers to the English nursery rhyme Oranges and Lemons.  The drink is therefore named (indirectly) after either St Clement Eastcheap or St Clement Danes, both churches in London.  The traditional recipe calls for equal parts orange juice and lemon juice served over ice in a highball glass.  There are many variations, in which the lemon juice is replaced with a sweeter drink (like lemonade), or even a carbonated citrus-flavored soft drink (like Sprite, 7-Up, or Fanta Lemon).

Supporting paragraphs: Rickey (cocktail) Greyhound (cocktail)
Answer: Rickey