$[$Wedding flowers$]$ Shae planned a backyard wedding for her daughter, Natalia, and contacted Flo's Flowers. Flo and Shae discussed terms for Natalia's wedding, including purple flowers, delivery at $3$:$00$ p$.$m$.,$ and a total cost of $$2,000.$ Flo e$-$mailed Shae a ten$-$page pre$-$printed contract in tiny print, which Shae thought was very long and confusing, but Flo had the best flowers in town. Shae glanced at the contract and noticed the price of "Three Thousand Dollars," which was not what they agreed. She typed a line through it and typed $"$ $$2K"$ in the margin along with her initials. Since she did not see anything about flower color, she added on the last page $"$As discussed, please provide purple flowers." She also noticed the delivery time was $5$:$00$ p$.$m$.$ Since they had agreed on $3$:$00$ p$.$m$.,$ she changed that item, and then typed her name at the bottom of the contract and e$-$mailed it back to Flo. When the big day came two months later, Flo's delivery truck did not arrive until $5$:$00$ p$.$m$.,$ and brought pink flower arrangements. The delivery workers gave Shae an invoice for $$3,000$ and demanded payment. Shae was livid and demanded they provide purple flowers, as agreed upon. Unfortunately, they had no flowers left in the delivery truck and the store was closed. Guests were arriving and Shae had no choice but to use the pink flowers. She begrudgingly handed over a check for $$2,000.$ The following day, Flo called demanding payment of the remaining one thousand dollars. Shae told her she would not pay because the flowers were pink, the price was wrong, and they arrived late. Flo referred Shae to Section $29$ of the contract which states, "Pigment may be redesigned at any time."

flo claims that "pigment redesign" in Section $29$ is regularly used in the flower business, and that she had every right "redesign" the color of the arrangements because she is a professional in the business. On which general guideline f contract interpretation is Flo relying?

Multiple Choice