In this task, you're given a question, a context passage, and four options which are terms from the passage. After reading a passage, you will get a brief understanding of the terms. Your job is to determine by searching and reading further information of which term you can answer the question. Indicate your choice as 'a', 'b', 'c', or 'd'. If you think more than one option is plausible, choose the more probable option to help you answer the question.

Example Input: Question: What is the average temperature of the body of water where the frontal low developed? Passage:A tropical disturbance moved westward offshore Nicaragua and was declared Tropical Depression Twenty-Four on October 15.. During the early afternoon of the next day, ship reports indicated the formation of a tropical depression close to land. The cyclone moved at a quick pace towards the west-northwest south of a warm-core ridge. Early on the morning on October 16, Roslyn became a tropical storm. By the morning of the October 17, Roslyn had developed into a hurricane south of Acapulco. A vigorous upper trough was deepening offshore Baja California, and Roslyn began to re-curve within a few hundred miles of Manzanillo. The system struck Mazatlán as a marginal hurricane on October 20. The low-level center rapidly dissipated, although a frontal low developed in the western Gulf of Mexico, which moved over southeastern Texas and later through the Mississippi Valley. The original upper-level circulation maintained its northeast movement, bringing rainfall to the Southeastern United States.
 Links: a. Mazatlán b. Acapulco c. Nicaragua d. Gulf of Mexico
Example Output: d

Example Input: Question: Which group ruled the area for a longer period of time, the Arabs or the Byzantines? Passage:The first permanent Arab settlement on Sicily occurred in 827, but it was not until Taormina fell in 902 that the entire island fell under their sway, though Rometta held out until 965. In that year the Kalbids established the independence of their emirate from the Fatimid Caliphate. In 1061 the first Norman liberators took Messina, and by 1071 Palermo and its citadel (1072) were captured. In 1091 Noto fell to the Normans, and the conquest was complete. Malta fell later that year, though the Arab administration was kept in place, marking the final chapter of this period. The conquests of the Normans established Roman Catholicism firmly in the region, where Eastern Christianity had been prominent during the time of Byzantine rule and even remained significant during Islamic period. Widespread conversion ensued, leading to the disappearance of Islam in Sicily by the 1280s. In 1245, Muslim Sicilians were deported to the settlement of Lucera, by order of Holy Roman Emperor Frederick II. In 1300, Giovanni Pipino da Barletta, count of Altamura, seized Lucera and exiled or sold into slavery its population, bringing an end to the medieval Muslim presence in Italy.
 Links: a. Messina b. Taormina c. Frederick II, Holy Roman Emperor d. Frederick II, Holy Roman Emperor
Example Output: b

Example Input: Question: What is the population of the city near where SH-66 meets SH-266 at its eastern endpoint? Passage:I-44/SH-66 cut diagonally through the city of Tulsa. In West Tulsa, Interstate 244 branches off to serve the downtown area. I-44/SH-66 follow the Skelly Drive through midtown. The highways interchange with the Okmulgee Beeline, the US-75 freeway before crossing the Arkansas River. The next freeway interchange is with the Broken Arrow Expressway, carrying US-64 and SH-51, followed by the Mingo Valley Expressway, carrying US-169 I-244 then merges with I-44 at its eastern terminus. I-44/SH-66 cross into Rogers County and the suburb of Catoosa, serving as the southern terminus of SH-167. SH-66 then splits off from I-44, initially following an old alignment of the Interstate where it transitioned into the Will Rogers Turnpike. SH-66 then downgrades to an expressway as it passes through Catoosa, home of the Blue Whale. Northeast of Catoosa, near Verdigris, SH-66 intersects SH-266 at its eastern terminus.
 Links: a. Oklahoma State Highway 167 b. West Tulsa, Tulsa c. U.S. Route 75 in Oklahoma d. Verdigris, Oklahoma
Example Output:
d