To solve this problem, we need to determine the partial pressures of oxygen (O₂) and carbon dioxide (CO₂) at the alveoli, which is the site of gas exchange in the lungs.$\newline$Let's analyze the options:$\newline \bullet$Option 1:$\newline$ - $pO₂ = 104$ mm Hg and $pCO₂ = 40$ mm Hg$\newline$ - These values are typical for the alveolar air, where oxygen is high and carbon dioxide is lower compared to venous blood.$\newline \bullet$Option 2:$\newline$ - $pO₂ = 40$ mm Hg and $pCO₂ = 45$ mm Hg$\newline$ - These values are more representative of venous blood, where oxygen is lower and carbon dioxide is higher.$\newline \bullet$Option 3:$\newline$ - $pO₂ = 95$ mm Hg and $pCO₂ = 40$ mm Hg$\newline$ - While these values are closer to arterial blood, they are not typical for alveolar air.$\newline \bullet$Option 4:$\newline$ - $pO₂ = 159$ mm Hg and $pCO₂ = 0.3$ mm Hg$\newline$ - These values are more representative of inspired air, not alveolar air.$\newline$Therefore, the correct partial pressures at the alveoli are:$\newline$Option 1: $pO₂ = 104$ mm Hg and $pCO₂ = 40$ mm Hg$\newline$This corresponds to the correct option, which is Option 1.