Common Cold (Viral Rhinitis): This is the most likely diagnosis given the symptoms of cough, runny nose, and eyes crusting. The common cold is a viral infection that affects the upper respiratory system and is characterized by these symptoms.

Influenza: Influenza or the flu can also present with similar symptoms, including cough, runny nose, and sometimes eye symptoms. It's more likely to be associated with fever and body aches.
Allergic Rhinitis: If the symptoms are persistent and related to exposure to allergens, allergic rhinitis could be a consideration. It typically presents with runny nose, sneezing, and itchy eyes.
Sinusitis: This could be a secondary bacterial infection following a viral upper respiratory infection, presenting with facial pain, nasal congestion, and purulent discharge.

Pertussis (Whooping Cough): Although less common due to vaccination, pertussis can present with a persistent cough and should be considered, especially in infants or those not vaccinated. It's crucial to diagnose and treat to prevent complications and spread.
Tuberculosis (TB): While less likely, TB can present with chronic cough and should be considered, especially in individuals with risk factors such as exposure, travel history, or immunocompromised status.
COVID-19: Given the current pandemic, COVID-19 should be considered in the differential diagnosis for any respiratory infection, especially if there's a history of exposure or travel.

Adenoviral Conjunctivitis: This can cause eye crusting and is associated with a highly contagious viral infection. It's less common but should be considered if there's significant eye involvement.
Mycoplasma Pneumonia: This atypical pneumonia can present with respiratory symptoms including cough and can be considered in cases where symptoms persist or worsen over time, especially in school-aged children or young adults.